Apple has just released OS X 10.8, Mountain Lion into the Mac App Store. The new operating system brings with it some 200 new features, including Notification Center, AirPlay Mirroring, Gatekeeper, and plenty more. If you're unsure about anything in Mountain Lion, you can find everything you need to know right here. You can snag it right now in the Mac App Store for $19.99. [OS X Mountain Lion]